1. Field of the Invention
The invention relates to a convertible motor vehicle roof with a roof column which can be transferred into a stowed position via a bearing mechanism when the motor vehicle roof is being opened.
2. Description of Related Art
German Patent DE 43 26 255 C1 and corresponding U.S. Pat. No. 5,542,735 disclose a motor vehicle roof which has, laterally on each side, a B column which is supported to be able to pivot and move lengthwise in a body-mounted guide which runs roughly horizontally over the rear axle in the lengthwise direction of the motor vehicle. One roof part is pivotally mounted on the B column and extends from the B column forward in the direction toward the front window. To open and lower the motor vehicle roof, first of all, the rear window is moved to under the roof part and the two rear triangular windows are lowered. Then, the B-column is moved as a unit to the rear together with the roof part and the rear window, lengthwise along the guide without being vertically lowered by means of a drive. In the rear position, the roof part is folded down towards the B column and in the direction of a stowage space. To completely lower the roof into a stowage space behind the seats, the B column is pivoted forward relative to the guide, the angular position of the roof part being adapted to the B column and moved forward by a certain amount.
The object of the invention is to devise a motor vehicle roof of the initially mentioned type with a bearing mechanism for the roof column which has kinematics which exhibits a simplified dynamic behavior for space-saving deposition of the roof column.
This object is achieved in the above mentioned motor vehicle roof in the invention by the bearing mechanism being designed to move the bottom end of the roof column forward with respect to the motor vehicle body and deposit it in its stowed position in a rearward pivoting motion around the bottom end.
This superimposed motion sequence composed of a forward motion and a pivoting motion makes it possible for the top end of the roof column, when the roof column is being deposited into its stowage position, to follow a curved path which can be established and which, according to the coordination of motion, for example, can lie on a vertical line or on a line which is slightly inclined relative to vertical, or initially executes a motion directed rearward with respect to the lengthwise axis of the motor vehicle, before the downward motion takes place. Initial rearward motion of the top end of the roof column can be feasible when the top end is to be moved away from the roof element to the rear when the roof is deposited after unlocking from the roof element. Basically, the bearing mechanism is suitable for any lateral roof column of a lowerable convertible roof which can be moved forward on its bottom on the body, thus especially for a C column or D column which forms, for example, the rear column in an all-terrain vehicle.
Preferably the bearing mechanism contains a linkage with a first four-bar mechanism which essentially executes forward motion and a second four-bar mechanism which is combined with it and which executes essentially pivoting motion. This linkage contains, for example, seven pivot joints and can be adjusted to the desired dynamic behavior by fixing the articulated positions and the rod lengths.
Motion is transferred from the linkage to the roof column, feasibly, by the middle rod of the second four-bar mechanism forming a roof column rod which is permanently connected to the roof column and which is pivoted when the first four-bar mechanism moves. Furthermore, the linkage can be made such that the front rod of the second four-bar mechanism is coupled to the front rod of the first four-bar mechanism, i.e., the rod which forms especially the ternary member.
The convertible motor vehicle roof can be made such that the roof element on the top section of the roof column is supported in a pivot joint. This roof element is then together with the roof column moved into the stowed position, its being pivoted via the pivot joint connection relative to the roof column. For pivoting, the roof element can have its own pivot drive which, for example, is located in the roof column or in the roof element. Alternatively, the roof element can be moved via an auxiliary rod arrangement with two coupled rods, the drive motion taking place via the coupling of one rod of the second four-bar mechanism.
Another preferred embodiment calls for the bearing mechanism to contain a linkage with a roof column rod which is permanently connected to the roof column and which has two spaced sliding joints which are movably guided on two guide rails which are spaced apart from one another and which are located roughly in the lengthwise direction of the motor vehicle, such that the roof column rod which is moved along the guide rails executes the forward displacement motion and the pivoting motion of the roof column. The guide rails form a comparatively flat unit for producing the forward displacement motion of the roof column. In doing so, the guide rail can initially run essentially linearly for the rear sliding joint and the other guide rail for the front sliding joint initially can run at an angle to the guide rail for the rear sliding joint such that the roof column rod executes an initial pivoting motion around the rear sliding joint
Feasibly, the two guide rails extend, as they continue, roughly parallel and are especially curved up essentially in agreement in their end sections. On the other hand, the two guide rails, as they continue, can also diverge, and with each of these embodiments, a certain dynamic behavior of the roof column rod, and thus, of the roof column can be established. Another alternative embodiment calls for the guide rail for the rear sliding joint to have an end curvature with a radius of curvature which roughly corresponds to the mutual distance of the two sliding joints and with a center of curvature which lies on the end stop for the front sliding joint.
In this version of the bearing mechanism, on the top end of the roof column, a roof element can also be pivotally mounted in a pivot joint. Feasibly, the roof element is moved via a 4-rod mechanism with motion derived from the moving roof column. But, it can also have its own drive.
The motor vehicle roof can have, in its forward section, at least one movably supported roof element which can be deposited in its stowed position by means of a deposition mechanism supported on the body, this deposition mechanism being coupled to the bearing mechanism of the roof column. Thus, two independent, movable roof units can be coupled with respect to the deposition motion and to the drive. In this way, the respective deposition motions are coordinated with one another so that collisions of the individual roof parts do not occur during deposition. In addition, one of the drives can be omitted by the coupling since the drive motion is transferred. Coupling can take place preferably mechanically, electrically or hydraulically. A simple mechanical coupling comprises a coupling rod which connects the bearing mechanism and the linkage of the roof column to the four-bar mechanism of the deposition mechanism of the front roof elements.
In the following, embodiments of the motor vehicle roof which is made as claimed in the invention are explained in detail with respect to the drawings.